Automatic winding mechanism for watch movements



H. THIEBAUD 2,536,615

AUTOMATIC WTNDTNG MECHANISM FOR WATCH MovEMENTs Jan. 2, 1951 Filed NOV. 27, 1948 llllllll lTfTlll ATTGRNEYg,

Patented Jan. 2, 1951 AUTOMATIC WINDING MECHANISM FOR WATCH MOVEMENTS Henri Thibaud, Biel, Switzerland Application November 27, 1948, Serial No. 62,298 In SwitzerlandDecember 27, 1946 (o1. ss-szi 1 Claim. l

This invention relates to an automatic winding mechanism having an oscillatory weight for energizing the main spring of watch movements.

Automatic winding mechanisms have already been proposed in which means are provided to permit the oscillatory weight to effect the winding operation in both directions of oscillation of the weight. These known devices require either complicated pawl mechanisms or wheels carried by pivoting levers to transform the two directions of movement of the oscillatory weight into a unidirectional movement of the winding train.

It is an object of the present invention to simplify the winding mechanisms which are effective in both directions oi oscillation of the weight, for the purpose of obtaining a more reliable operation, to realize a reduced space with respect to known devices and thereby a decrease of the ilrst cost of the watch movement.

According to the present invention, the automatic-winding mechanism comprises a pinion which always meshes with a wheel driven in both directions by the oscillations of said weight, this pinion being mounted to effect a limited reciprocating movement owing to the tangential forces exerted on it by the said wheel, between two extreme positions in which the pinion meshes according to the direction of movement of the oscillatory weight with one or the other of two wheels of a winding train, so that the winding is eiiected in both directions of movement of the oscillatory Weight.

The accompanying drawing shows by way of example a preferred embodiment of the invention.

Fig. 1 is a plan view of the winding mechanism, partially drawn in section.

Fig. 2 is a sectional view according to the broken line II--II of Fig. 1 drawn to a smaller scale.

The oscillatory weight I can oscillate about a iixed axis 2 disposed at the centre of the movement. The movement is only dlagrammatically represented and comprises the usual frame constituted by the plate 3 and the bridges 4 supporting the main spring barrel 5 with its shaft 6.

The winding train is carried by a cage formed by two supplementary plates 1 iixed to the bridges. The axis 2 of the oscillatory weight I is provided with a ilange 8 by which it is screwed to the cage l. The hub of the oscillatory weight engaged on the axis 2 carries a pinion 9 which constantly meshes with a pinion IIJ having its axis or pivot shaft engaged at each end in a slot I I and Il', respectively, of the two supplementary plates of the cage 1, these slots having the shape of a circular arc, the centre of which is situated in the axis 2. As disclosed in Fig. 2, pinion I0 is provided with shoulders which bear against the inner faces of the two plates 'I to confine the pinion axially between them. Thus, this pinion I0 can effect an oscillatory reciprocating movement from one end of the slots II to the other end while always remaining in mesh with the teeth of the central pinion 9.

On a square portion of the barrel axis 6 is adjusted the barrel ratchet I2 with which cooperates the winding pawl I3 engaged on a pin I 4 carried by the ratchet driving wheel I5 which is loosely mounted on the barrel axis. The wheel I5 engages with a pinion I6 mounted on the axis of the wheel Il which meshes in turn with the pinion I8. This latter is mounted on the axis of the wheel I9 which is in mesh with a similar wheel 20 with which cooperates a retaining pawl 2I permitting the rotation of the wheel 20 only in the direction indicated by the arrow. When the oscillatory pinion I0 is at the right hand end of the slot I I, as indicated in Fig. 1, it meshes with the Wheel 20, while when it meshes with the wheel I9 it is at the other end of the slot Il.

When the oscillatory weight I moves in the direction of the arrow a the central pinion 9 turns in the same direction and by the intermediary of the reciprocating pinion I0 it drives the wheel 20 in the direction indicated by the arrow. The movement of the wheel 20 is transmitted by the winding train I9, I8, Il, IB to the ratchet driving wheel I5, the pawl I3 of which drives the ratchet I2 of the barrel axis E. When the oscillatory Weight I moves in the direction of the arrow b, the tangential effort exerted by the central pinion 9 on the reciprocating pinion IIJ moves this latter towards the other end of the slot Il. The pinion I0 abandons the teeth of the wheel 20 to come into engagement with those of the wheel I9 and causes then the wheel I9 to turn in the direction of the indicated arrow, namely in the same direction as before when it was driven by the wheel 20, and the barrel is also wound up. Upon a further change of direction of rotation of the oscillatory weight I in the direction of the arrow a, the pinion Il! moves again towards the'right in Fig. 1 and meshes with the wheel 20. Accordingly the barrel is wound up in both directions of movement of the oscillatory weight I by a simple reciprocating pinion I0 adapted to move into one or the other of two positions at the ends of the slot l l without necessity to provide pivoting levers or complicated pawl mechanisms which cucumber the watch movement.

said weight to effect an oscillatory movement of rotation of the Wheel, responsive to the oscillations of said weight, a ratchet driving Wheel for winding up the main spring, a train of winding wheels for rotating the ratchet driving wheel, a frame for supporting the Wheels of the winding train, said frame including a pair of spaced plates, each wheel being journalled at each end in oppos-f ing plates of the frame, said plates having corresponding arcuate slots one in each plate with their centers of curvature situated in the axis of rotation of said driving Wheel, and a pinion con stantly in mesh with said driving Wheel and have ing a pivot shaft extending'outwardly on opposite sides thereof, shoulders on the pivot shaft bearing against the inner faces of the two plates, the. extensions of said pivot shaft being respec- 'tivelyengaged in said slots to constitute, together with the shoulders and the meshing of said pinion and said driving wheel, the sole axial and lateral 'support of said pinion; whereby tangential forces exerted on the pinion by said oscillatory driving wheel produce la limited reciprocating motion of the pinion between two extreme positions in said slots, the said slots constituting a guideway for tracking said pinion in a path arcuate relative the axis of rotation of said driving Wheel and for defining pivot shaft stops at extremes thereof, said train of winding Wheels including two wheels meshed to rotate oppositely, one of said wheels being mounted in driven engagement with said reciprocatory vpinion in one of the stop-engaging positions thereof and the other of said wheels being mounted in driven engagement with the pinion in the 'other stop-engaging position thereof.

HENRI THIEBAUD.

`REFERENES CITED The following references are of record in the ii-lc of this patent:

UNITED STATES PATENTS Kamper Name 'Date' :310,531 YLorain Api-1.23, i929 2,399,131 Matter Apr. 23., 1946 FOREIGN PATENTS Number Country Date 592,986 Germany Feb. 19, 1934 

